Deutsche Bank is considering selling shares to boost capital later this year, the German lender’s latest attempt to resolve concerns about its financial strength, according to people familiar with the matter.

The potential capital hike, which Deutsche Bank executives haven’t yet decided whether to pursue, would be on top of €1 billion to €2 billion ($1.38 billion to $2.77 billion) of capital-boosting hybrid bonds that it plans to issue in coming weeks, these people said.

Germany’s largest bank, which is to announce first-quarter earnings on Tuesday, late last year increased its core capital ratio to 9.7%, up from 7.8% a year earlier. That ratio is a key measure of balance-sheet strength that compares equity to assets that are weighted by their riskiness.

Deutsche Bank executives have previously stressed the bank was focusing on strengthening its capital cushions without tapping shareholders for fresh equity, through a combination of holding on to earnings it generates and issuing about €5 billion of hybrid bonds by 2015. But a new regulatory charge being imposed by the European Union’s European Banking Authority will push the ratio down to around 9% later this year, analysts expect. Such a swing would likely place Deutsche Bank at the lower end of its international peers.

In response, Deutsche Bank is considering issuing new shares before the European Central Bank starts supervising the eurozone’s largest banks in November, said the people familiar with the matter. The analysis is ongoing and the bank still would prefer to shed unwanted assets rather than issue new shares, one of these people said.

“A capital increase isn’t a taboo anymore, but it’s preferred to make [the targets] without one,” one of these people said.

The ECB is currently scrutinising whether banks are valuing their assets realistically. The banking authority will later this year conduct stress tests to check the robustness of eurozone banks.

Deutsche Bank’s current strength measures “are in line with or slightly weaker than those of most other European banks at this stage,” said Eva Olsson, an analyst at Mitsubishi UFJ Securities. She noted that the bank faces potential costs from ongoing lawsuits and has “relatively weak earnings” that “could…result in a need to raise equity.”

Chief Financial Officer Stefan Krause in January said the ECB, in its new role as eurozone banking supervisor, will “likely accelerate the convergence of regulatory practice across the eurozone” and that he expected potential downward pressure on Deutsche Bank’s equity capital ratio in the coming quarters.

Krause said the bank remained committed to achieving its target of a 10% capital ratio by the end of the first quarter 2015.

The bank is meanwhile preparing to issue a first tranche of a hybrid bond to further shore up its balance sheet. Krause said last year that the bank planned to issue around €5 billion in these instruments to improve its leverage ratio, which is a measure of total assets to loss absorbing capital.

Olsson at Mitsubishi UFJ said she believed Deutsche Bank could issue the bonds shortly after publishing first quarter results, scheduled for Tuesday. She added that most issuances had a volume of EUR1 billion to EUR2 billion and that this would be a size Deutsche Bank would likely consider as well. Deutsche Bank recorded a leverage ratio of 3.1% at the end of last year, just north of the 3% minimum threshold.

In January Krause said the bank was committed to achieving its target of a 10% capital ratio by the end of the first quarter 2015.

--write to Eyk Henning at eyk.henning@wsj.com and Madeleine Nissen atMadeleine.Nissen@wsj.com